safe to use X200 without battery?

[eosme]

is it safe to use the laptop plugged in via AC adapter without the battery pack installed?

any worries to surge or anything like that?

[EOMtp]

Aside from the concern that the notebook will turn off in the middle of whatever one was doing if one lost power/disconnected the power cord, there is no "safety", i.e., electrical or electronic, concern in using the notebook without a battery. The power adapter isolates the PC from external power; the battery does not play a role in protecting the notebook from external electrical events.

[eosme]

Aside from the concern that the notebook will turn off in the middle of whatever one was doing if one lost power/disconnected the power cord, there is no "safety", i.e., electrical or electronic, concern in using the notebook without a battery. The power adapter isolates the PC from external power; the battery does not play a role in protecting the notebook from external electrical events.

ok, thanks. just wanted to double check because i had always kept my battery plugged in in my previous laptop and ended up killing the battery.

just don't want that to happen again.

[EOMtp]

... i had always kept my battery plugged in in my previous laptop and ended up killing the battery.

That laptop was not a Thinkpad! Some manufacturers' battery charging circuits "pump" juice into the battery continuously whenever the chargers are connected to the laptop. That continuous "topping off" -- even when the batteries are full -- is what destroys the batteries. The charging circuits of Thinkpads do not behave that way. You don't have to disconnect the battery on a Thinkpad to keep the battery healthy.

[eosme]

you're right it was a toshiba portege 7010ct when it first came out. this is my first thinkpad and i have to say.. i'm loving it!

[dr_st]

The charging circuits of Thinkpads do not behave that way. You don't have to disconnect the battery on a Thinkpad to keep the battery healthy.

You are right, however there remains another (smaller) issue, and that's keeping the battery always charged at 100% (or close to it). It is generally accepted that the battery degrades faster this way than if the charge is kept around 40-50%. Now, how many people, with Thinkpads or not, actually change their thresholds to keep the battery around that 40-50% mark when inside the laptop?

[eosme]

You are right, however there remains another (smaller) issue, and that's keeping the battery always charged at 100% (or close to it). It is generally accepted that the battery degrades faster this way than if the charge is kept around 40-50%. Now, how many people, with Thinkpads or not, actually change their thresholds to keep the battery around that 40-50% mark when inside the laptop?

so you mean when the battery meter drops down to 50% that's when you charge?

today while i was backing up using acronis, my battery went down to only lasting another 58 mins. and then it "stretched" giving me a couple more. what's that all about?

also, is it not good to use ur battery till it's all deplited before charging?

[dr_st]

so you mean when the battery meter drops down to 50% that's when you charge?

No, not quite. I meant that if the PC is used on AC power 99% of the time, and the battery is essentially idling (not charging, not discharging), then it's better for it to idle around 50%, and not around 100% (which is what happens in most laptops). The problem with this approach, is that when you do need the battery on short notice, it only holds 50% of the charge.

also, is it not good to use ur battery till it's all deplited before charging?

Constant frequent charges/discharges of the battery are generally accepted as bad practice for Li-ion batteries. However, once in a while (every few weeks to few months), it is advised to do a couple of such full charge-discharge cycles, to recalibrate the battery meter.

[wolssiloa]

You also have to remember the CPU will not run at the highest clock speed if there is no battery connected. For instance my X200s with a SL9400 will drop to about 1596 MHz if there is no battery. I'm not sure what the logic to this is?

[dr_st]

The logic is to prevent pulling too much juice from the power supply, thus damaging it. Usually happens only with 65W power adapters. With 90W it should still allow the CPU to run at full speed.

[wolssiloa]

The logic is to prevent pulling too much juice from the power supply, thus damaging it. Usually happens only with 65W power adapters. With 90W it should still allow the CPU to run at full speed.

With both the battery and AC plugged in, doesn't the battery sit idle though? Wouldn't it be using the same amount of power from the AC?

[dr_st]

With both the battery and AC plugged in, doesn't the battery sit idle though? Wouldn't it be using the same amount of power from the AC?

With the battery connected, in times of need, the laptop can pull some juice from the battery if the power supply does not provide enough.

[raiaken]

It's important to note, however, that the AC Adapter doesn't shield the laptop from voltage spikes despite it being an AC/DC transformer. I was on a Deutsche Bahn train a few months ago and the voltage spiked past 240V and fried the USB and Audio chipsets on my X40. Still, having a battery didn't help.

[Esben]

Constant frequent charges/discharges of the battery are generally accepted as bad practice for Li-ion batteries. However, once in a while (every few weeks to few months), it is advised to do a couple of such full charge-discharge cycles, to recalibrate the battery meter.

In my X60s the battery is very often used, and charged to full again. The battery has about 200 cycles, and holds 101 % capacity of the original. I believe its more harmfull to keep a battery fully charged and topped off, than to often unplug the laptop and let it run battery down to 10-20%.

[dr_st]

How old is your battery (manufacturing/first use date)?

Have you ever charged it down to 0% to see how much it really holds (and not how much it thinks it holds)?

[eosme]

How old is your battery (manufacturing/first use date)?

Have you ever charged it down to 0% to see how much it really holds (and not how much it thinks it holds)?

how do you do that? i thought maybe perhaps the power manager software is old, but i have the latest version 2.5, so the battery bar should be correct.

but then i noticed in the power manager, you can resent the battery meter by leaving the AC plugged in and it will charge to full and discharge and then charge to full.

maybe it's my meter that's throwing things off?

also.. which # are the manufacturer date code?

[dr_st]

Normally I check for these things in the power manager, battery information tab. But the new power manager versions have the UI redone, so I don't know where exactly to look.

[eosme]

Normally I check for these things in the power manager, battery information tab. But the new power manager versions have the UI redone, so I don't know where exactly to look.

i found out the battery information.

img]http://btx52g.bay.livefilestore.com/y1p ... 20cell.JPG[/img]

[dr_st]

Strangely it doesn't show full charge capacity. What is it with people and redesigning things that aren't broken in stupid ways...

[eosme]

Strangely it doesn't show full charge capacity. What is it with people and redesigning things that aren't broken in stupid ways...

yeah i know.. sigh, guess i have to live with it...